218308456 has 32 divisors (see below), whose sum is σ = 431956800. Its totient is φ = 103227520.

The previous prime is 218308451. The next prime is 218308459. The reversal of 218308456 is 654803812.

It is a happy number.

218308456 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×218308456² = 95317163922207872, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (218308451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9711 + ... + 23041.

It is an arithmetic number, because the mean of its divisors is an integer number (13498650).

Almost surely, 2^218308456 is an apocalyptic number.

It is an amenable number.

218308456 is a deficient number, since it is larger than the sum of its proper divisors (213648344).

218308456 is a wasteful number, since it uses less digits than its factorization.

218308456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13449 (or 13445 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 37.

The square root of 218308456 is about 14775.2650060836. The cubic root of 218308456 is about 602.1298895967.

The spelling of 218308456 in words is "two hundred eighteen million, three hundred eight thousand, four hundred fifty-six".